Field of the Invention
This disclosure relates to a power control system and a power control method and, more particularly, to a power control system and a power control method which allow the computer system and the power system of a computer device separately stay in different operating modes.
Description of the Related Art
In a common computer device, a central processing unit (CPU) is regarded as the brain of a computer device for processing the core tasks of the computer device. In particular, a clock frequency that the CPU is operating on is an important performance indicator. The higher the clock frequency is, the faster the computer device can process instructions. When manufacturing CPUs in mass production, the CPU suppliers usually guarantee the clock frequency under normal operation in the universal product specification; therefore, the CPU is actually capable of operating normally at a higher clock frequency. As a result, some advanced users will try to use the CPU with a higher clock frequency, or called overclocking, so as for the computer device to reach a better performance. Some CPU suppliers, like Intel, even provide the CPU products with a frequency multiplication-locked type and a frequency multiplication-unlocked type to meet different users' needs.
Please refer to FIG. 1, where FIG. 1 is a block diagram of a computer device in accordance with the prior art. A conventional computer device 100 in accordance with the prior art shown in FIG. 1 includes a computer system 110 and a power system 130. The computer system 110 includes related hardware components required for the operation functions of the operating system (OS) of the computer device 100, where the hardware components may include a CPU, a southbridge chipset, or a northbridge chipset, etc. The power system 130 includes a plurality of voltage regulators for providing one supply voltage to each component of the computer device 100, where the components may include a HD drive, a CD-ROM drive, a display card, or a cooling system. In the conventional computer device 100, the southbridge chipset is responsible for controlling power. According to the standard of the advanced configuration and power interface (ACPI), the operation of a computer device in the aspect of power management can be divided into the following modes.
S0 mode: a normal operation state. In this state, all components of the computer device operate and receive electric power normally.
S1 mode: a first standby state. In this state, the central processing unit (CPU) stops operating, but all other components of the computer device maintain receiving electric power normally.
S2 mode: a second standby state. In this state, the CPU of the computer device powers off, but all other components of the computer device maintain receiving electric power.
S3 mode: a hibernation state. In this state, all components of the computer device stop operating except the memory of the computer device.
S4 mode: a sleep state. In this state, all components of the computer device stop operating after the information in the memory are written into the hard disk or other non-volatile memory devices.
S5 mode: a power-off state. In this state, all components of the computer device stop operating after executing a power-off procedure.
Therefore, when receiving a shutdown signal to enter S5 mode from S0 mode and the operating mode is in S0 mode, the computer system 110 starts to execute the power-off procedure. After the procedure is complete, the southbridge chipset turns off most of the voltage regulators of the power system 130, including the regulators providing supply voltages to the components of the computer device 100 such as the HD drive, the CD-ROM drive, the display card, or the cooling system, and only some few voltage regulators that are required to operate maintain to supply the voltages. For example, in using a power supply complying with ATX standard, after the computer device 100 enters S5 mode, only the set of 5VSB voltage for supplying supply voltages to an embedded controller (EC) is still operating.
However, when the CPU is operated with overclocking frequency, the computer device 100 often spontaneously enters the power-off state and then resumes powering on again. In other words, the computer device 100 switches between the S0 mode and the S5 mode back and forth. This situation causes the components of the computer device 100 such as the HD drive, the CD-ROM drive, the display card, or the cooling system to power off and then power on again frequently. This frequent on-and-off operation shortens the service lifetime of the components of the computer device. In addition, the on-and-off operations in some components such as the operation of motors or fans also cause extra noise.
More importantly, when the CPU is operated with overclocking frequency, the CPU often generates huge heat. The heat dispassion efficiency of the cooling system of the computer device plays an important factor in keeping the whole systems stable and in extending the service lifetime of the components of the computer device. Hence, when the computer device 100 shuts down during the overclocking frequency state, which causes the cooling system to power off, the temperature inside the computer device 100 increases because the cooling system is unable to operate.
Therefore, there is a need to maintain the operation of the cooling system in the computer device during the overclocking frequency state, so as for the computer device 100 to increase the performance and extend the service lifetime of the computer device 100.